1. Field of the Invention
This invention relates to a method of and an apparatus for inspecting a work, and more specifically to a method of and an apparatus for inspecting each of works wherein a checking program for inspecting the work is produced and each work to be checked is inspected in accordance with the produced checking program.
2. Description of the Background Art
An apparatus for inspecting a unit comprised of a plurality of parts has heretofore been produced on a site where a vehicle or the like is manufactured.
A criterion for judging or determining whether or not the unit is faulty, has been set in advance upon design of the unit. However, a specific inspecting method for satisfying the criterion should be decided on a production site.
Therefore, the following steps are required to produce an inspecting apparatus. That is, a plurality of sensors are attached to a unit to be inspected and data are read by the respective sensors using a waveform observing device or the like (measuring step). A system engineer analyzes the read data on his/her desk, selects the optimum inspection point from the result of analysis, sets the timing for reading the data and sets a decision value for determining whether or not the unit at the optimum inspection point is faulty (decision value producing step). Further, an inspecting method is decided based on the set decision value (inspecting method producing step).
In accordance with a manufacturing specification for the inspecting apparatus produced based on the inspecting method, a checking program for inspecting each unit is created by a software engineer and the hardware for a dedicated inspecting apparatus having a microcomputer incorporated therein is manufactured. The produced checking program is stored in the inspecting apparatus and each unit to be checked is inspected.
In the conventional inspecting method however, it is necessary to provide the waveform observing device in the measuring step. Further, a program producing device is required to create the checking program. Thus, a number of devices should be prepared before the creation of the checking program. Therefore, the arrangement of the devices is cumbersome.
Further, when the decision value for determining whether or not the unit is faulty is set in the decision value producing step, the measured data obtained in the measuring step are represented in the form of a graph, for example, and a process for analyzing the measured data is effected on the desk. Therefore, a problem arises that much time is required for the analytic process.
When the measured data are insufficient to decide the decision value upon analytic process, measured data should be obtained by executing the measuring step again, for example. Further, the system engineer executes the measuring step, the analysis and the decision value producing step under trial and error. Therefore, a lot of time is required.
Furthermore, since the inspecting method and the checking program are dedicatedly produced for each unit to be inspected, a problem arises that the inspecting method and the checking program should depend on the system engineer and the software engineer both having special knowledge when the shape of the unit is partially changed or each time the inspecting method is corrected.